Don't run 100 mile weeks, but building towards mid 80s to 90. Here is what the schedule generally looks like.
Mon/Wed: Get up at 6:05, take 6:36 train to Grand Central, at desk by 7:15. Work all day, maybe sneak out for a run, maybe not. Regardless, take either the 5:56 or 6:18 train home. Get home between 6:35 and 7:00, eat dinner, put kids to bed at 8:00, and if I didn't run during the day, Mon run 7 miles and Wed run 9-10 miles. Shower, watch TV with wife for an hour, fall asleep.
Tue, Thur, Fri: Get up at 5:45AM, take 6:02AM train to Harlem 125th Street Get off at 6:27AM and run for an hour to work. At desk by 7:45-50 on these days. Bring work clothes and put in foot locker at gym at work on Mon and Wed (for Tue and Thur/Fri). On these days I try and sneak out of work to go for a quick jog either at lunch or late afternoon as the markets die down. Take the 5:56 or 6:18 train home. Sometimes I can't do the afternoon run from work, so will do at 8:00 after putting kids to bed. Sometimes skip it.
Saturday and Sunday I run usually when the kids are napping. Run a long workout where the total quantity can be as much as 15 miles on Sat and up to 20 on Sun.
That's at least the schedule right now. My mileage will fluctuate depending on if I can run during work hours and if not, if I can motivate to go at 8:00 knowing I have to get up and do it the next morning early.
As far as energy levels... I'm not a good sleeper. So more then the running, this kills me. I'll be in bed for 8 hours, but frequently only actually sleep 4-5 hours. My energy wanes throughout the day, but not enough to effect work performance. I usually drink 2 cups of coffee, and am pretty grumpy if I don't. Don't really watch what I eat, but try and be relatively healthy. My metabolism goes crazy when I run a decent amount, so I just try and avoid wasting away.
The key is to stay busy at work. As soon as it slows down (like in the summers) its tough to keep your head in it. You find that the tiredness leads to daydreaming (usually about running) and lethargy. If you can motivate to create some project for yourself during that time, it helps to alleviate tiredness.
I also find I go for a walk outside almost every day for 15 minutes to clear my head and get fresh air. This helps to wake me up and keep me focused.